Clean stale certbot data before SSL acquisition attempt

If a previous certbot run created live/archive/renewal dirs but
failed to complete, the next attempt would choke on the existing
'live directory'. Now cleans these before each attempt.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

nginx/entrypoint.sh

@@ -47,6 +47,11 @@ else
 
     echo "Requesting Let's Encrypt certificate for ${DOMAIN}..."
 
+    # Clean stale certbot data from any previous failed attempt
+    rm -rf "/etc/letsencrypt/live/${DOMAIN}" \
+           "/etc/letsencrypt/archive/${DOMAIN}" \
+           "/etc/letsencrypt/renewal/${DOMAIN}.conf" 2>/dev/null || true
+
     # Attempt certificate acquisition
     if certbot certonly --webroot \
         -w /var/www/certbot \